在 UWP 上以 Json 的形式发送请求

Question

我已经使用已部署的 Web 服务部署了 AzureML 发布的实验。我尝试使用 sample code provided in the configuration page, but universal apps do not implement Http.Formatting yet, thus I couldn't use postasjsonasync.

我尝试尽可能地遵循示例代码，但我得到的状态码是 415 "Unsupported Media Type"，我在做什么错误？

var client = new HttpClient();
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);
// client.BaseAddress = uri;

var scoreRequest = new
{
            Inputs = new Dictionary<string, StringTable>() {
                    {
                        "dataInput",
                        new StringTable()
                        {
                            ColumnNames = new [] {"Direction", "meanX", "meanY", "meanZ"},
                            Values = new [,] {  { "", x.ToString(), y.ToString(), z.ToString() },  }
                        }
                    },
                },
            GlobalParameters = new Dictionary<string, string>() { }
 };
 var stringContent = new StringContent(scoreRequest.ToString());
 HttpResponseMessage response = await client.PostAsync(uri, stringContent);

非常感谢

Answer 1

您需要将对象序列化为 JSON 字符串（我建议使用 NewtonSoft.Json 以使其更容易）并相应地设置内容类型。这是我在我的 UWP 应用程序中使用的实现（请注意 _client 是 HttpClient）：

    public async Task<HttpResponseMessage> PostAsJsonAsync<T>(Uri uri, T item)
    {
        var itemAsJson = JsonConvert.SerializeObject(item);
        var content = new StringContent(itemAsJson);
        content.Headers.ContentType = new MediaTypeHeaderValue("application/json");

        return await _client.PostAsync(uri, content);
    }

在 UWP 上以 Json 的形式发送请求

Send request as Json on UWP

c#

json

dotnet-httpclient

azure-machine-learning-studio

uwp